Setting aside the first resurrection for a moment(1000 years earlier than I will quote in a moment from revelation)
And this is the will of him who sent me, that I shall lose none of all those he has given me,
but raise them up at the last day. For my Father’s will is that everyone who looks to the Son and believes in him shall have eternal life,
and I will raise them up at the last day.”
John 6:39&40
When is the last day?
Then I saw a great white throne and him who was seated on it. The earth and the heavens fled from his presence, and there was no place for them.
12 And I saw the dead, great and small, standing before the throne, and books were opened. Another book was opened, which is the book of life. The dead were judged according to what they had done as recorded in the books.
13 The sea gave up the dead that were in it, and death and Hades gave up the dead that were in them, and each person was judged according to what they had done.
14 Then death and Hades were thrown into the lake of fire. The lake of fire is the second death.
15 Anyone whose name was not found written in the book of life was thrown into the lake of fire. Rev20:11-15
Then I saw “a new heaven and a new earth,”[a] for the first heaven and the first earth had passed away, and there was no longer any sea.
2 I saw the Holy City, the new Jerusalem, coming down out of heaven from God, prepared as a bride beautifully dressed for her husband.
3 And I heard a loud voice from the throne saying, “Look! God’s dwelling place is now among the people, and he will dwell with them. They will be his people, and God himself will be with them and be their God.
4 ‘He will wipe every tear from their eyes. There will be no more death’[
b] or mourning or crying or pain,
for the old order of things has passed away Rev21:1-4
The last day, is the last day of this present earth, before it passes away. And if we note Rev20:15, it will include the saved and unsaved.